The present invention relates to a high pressure gas discharge valve device for a safety air bag for use in a motor vehicle.
The high pressure gas for inflating the safety air bag to protect the occupants in the motor vehicle upon collision thereof is hermetically contained in a high pressure gas container. The container is provided with a gas discharge valve at the opening portion for blowing out the gas. The opening is normally closed by the valve so that no leakage of the gas occurs from the container. The gas discharge valve comprises a blocking cock having a sealing disk. In hitherto known blocking cocks, the sealing disk is formed with a circular groove extending along the periphery and a plurality of straight grooves passing through the center of the disk and intersecting with one another. The blowing out of the high pressure gas from the container takes place when the sealing disk is ruptured or destructed under exploding force automatically produced by a detonator upon the collision of the vehicle. However, in the case of the hitherto known valve structure, the sealing disk is nearly partially ruptured, especially, only the crossed section of the grooves is easily broken, so that only a small aperture is available for the jetted high pressure gas with the flow rate thereof being restricted. Consequently, a rapid inflation of the air bag can not be accomplished with the conventional valve structure.